Growth and yielding of peach and nectarine trees after intensive regenerative pruning

Studies were carried out in the years 2006-2008 in Przybroda near Poznań. The objects of the studies included seven-year-old peach trees of the cultivars ‘Harnaś’, ‘Reliance’, ‘Vinegold’ and ‘Early Blaze’ nectarine. The trees were strongly damaged by frost during the winter of 2005/2006. In May 2006, intensive regenerative tree pruning was carried out. Two treatments were applied: 1. The control with no pruning treatment, where only sanitary pruning was performed; 2. Trees were pruned at the height of 1.5 m and the shoots, which were developing below that height line, were left not pruned. The pruning treatment caused the development of an abundant number of longshoots, which are valuable for fruiting, in the central part of the crowns, with a diameter greater than 0.5 cm in comparison with the control trees. In the second year after pruning, spring ground frost destroyed the flowers and fruit buds and only single fruits were harvested. In the third year after pruning, the trees bloomed very abundantly and set fruits, therefore thinning was necessary. The yield was high and in most cases, it was equal independent of the tree pruning method, giving up to 18-19 kg per tree. Differences occurred only between the particular cultivars where the yield oscillated between 11 and 25 kg per tree. The best yielding was shown by ‘Vinegold’ (over 24 kg), then ‘Harnaś’ (21 kg), while the poorest yield was obtained from ‘Reliance’ (about 11 kg).